Changes in autism spectrum disorder prevalence in 4 areas of the United States.

BACKGROUND: We sought to describe autism spectrum disorder (ASD) population characteristics and changes in identified prevalence across 3 time periods. METHODS: Children with a potential ASD were identified through records abstraction at multiple sources with clinician review based on Diagnostic and Statistical Manual (DSM-IV-TR) criteria. Multisite, population-based data from the Autism and Developmental Disabilities Monitoring (ADDM) Network were analyzed from areas of Arizona (AZ), Georgia (GA), Maryland (MD), and South Carolina (SC). Participants were 8-year-old children (born in 1992, 1994, or 1996) in 2000, 2002, or 2004 (and children born in 1988 residing in metropolitan Atlanta in 1996) who had been evaluated for a variety of developmental concerns at education and/or health sources. RESULTS: From 2000 to 2004, the identified prevalence of the ASDs per 1,000 8-year-old children showed significant increases of 38% in GA and 72% in MD and a nonsignificant increase of 26% in AZ. ASD prevalence was relatively stable in SC with a nonsignificant decrease of 17%. Males had a higher identified prevalence of ASD in all years. Increases among racial, ethnic, and cognitive functioning subgroups varied by site and surveillance year. More children were classified with an ASD by community professionals over time, except in AZ. CONCLUSIONS: There was a trend toward increase in identified ASD prevalence among 8-year-old children who met the surveillance case definition in 3 of the 4 study sites from 2000 to 2004. Some of the observed increases are due to improved ascertainment; however, a true increase in ASD symptoms cannot be ruled out. These data confirm that the prevalence of ASDs is undergoing significant change in some areas of the United States and that ASDs continue to be of urgent public health concern.

Emergency medical services data for cardiovascular disease surveillance, program planning, and evaluation in Maine.

Rapid access to medical treatment is a key determinant of outcomes for cardiovascular events. Emergency medical services (EMS) play an important role in delivering early treatment for acute cardiovascular events. Attention has increased on the potential for EMS data to contribute to our understanding of prehospital treatment. Maine recently began to explore the possible role of EMS data in cardiovascular disease surveillance and cardiovascular health program planning and evaluation. We describe the Maine EMS data system, discuss findings on ease of data use and data quality, provide a sample of findings, and share how we plan to use EMS data for program planning and evaluation of community-level interventions and to partner with EMS provider organizations to improve treatment. Our objective is to increase understanding of the promise and limitations of using EMS data for cardiovascular disease surveillance and program planning and evaluation.

Using state lead poisoning surveillance system data to assess false positive results of capillary testing.

OBJECTIVE: The purpose of this study was to determine the false positive percentage of capillary blood lead screening in a statewide surveillance system and to explore potential predictors of false positive results. METHODS: Data were all blood lead tests of 0-5 year old children in Maine during 2002-2003. We determined the proportion of children with elevated (>/=10 microg/dL) capillary test results who received a venous confirmatory test, and calculated the percentage of false positive tests, defined as a capillary test of >/=10 microg/dL with a confirmatory venous test of <10 microg/dL. Multivariable binomial regression was used to determine whether capillary blood lead level and length of time between capillary and venous tests predicted false positive results, after controlling for potential confounders. We also examined the positive bias of the capillary test among both false positive and true positive results. RESULTS: Seventy-three percent of elevated capillary screening tests (2.2 percent of all capillary screening tests) were false positives. False positive results were less likely for capillary levels of 15-19 microg/dL (RR=0.78; 95% CI 0.5-0.92) and 20 microg/dL or above (RR=0.83; 95% CI 0.71-0.96) compared to 10-14 microg/dL. The percentage of false positives did not vary by interval between screening and confirmatory tests. The capillary test exhibited a positive bias compared to the venous test, even among true positive results. CONCLUSIONS: False positive results may have been caused by sample contamination, rather than laboratory error or true variation in blood lead level between screening and confirmatory tests. Capillary screening could be improved by training in proper sample collection methods.

Prevalence and selected characteristics of childhood vision impairment.

The objective of this study was to examine the descriptive epidemiology of vision impairment among 6- to 10-year-old children in metropolitan Atlanta, Georgia, USA. Children with vision impairment (n=310; 42% black, 56% white; 57% male, 43% female), defined as a best corrected visual acuity in the better eye of 20/70 or worse, were identified through the Metropolitan Atlanta Developmental Disabilities Surveillance Program. The overall prevalence was 10.7 per 10,000 children. Fifty-nine percent had low vision; nearly two-thirds had coexisting disabilities. Educational program varied by vision impairment severity and presence of coexisting disabilities. The common presence of coexisting disabilities emphasizes the importance of multidisciplinary services. The inclusion of case ascertainment sources other than vision impairment classes is critical to ensure an accurate prevalence rate and unbiased description of children with vision impairment.